1. Field of Invention
This invention relates to a terminal, for example a terminal that is crimped on an electric wire of a vehicle and secured to a mating member by a bolt.
2. Description of Related Art
Heretofore, terminals are connected to ends of electric wires arranged in an automobile. Some terminals are secured to a vehicle body by a bolt in order to ground an electric wire to the vehicle body. Other terminals that are connected to high current electric wires are connected to equipment or the like by a bolt.
For convenience of explanation, a conventional terminal will be described by referring to FIGS. 15A to 16B. FIG. 15A is a perspective view of a conventional terminal in a position before being secured to a vehicle body. FIG. 15B is a perspective view of the conventional terminal in a position after being secured to a vehicle, illustrating a problem in the terminal. FIG. 16A is a plan view of another conventional terminal. FIG. 16B is a perspective view of this other conventional terminal in a position after being secured to a vehicle, illustrating a problem in the terminal.
For example, in order to ground electric wires, as shown in FIG. 15A, ends of electric wires W are connected to terminals 1a and 1b by crimping the terminals 1a and 1b to the ends of the electric wires W. As shown in FIGS. 15A and 15B, the terminals 1a and 1b are overlapped on each other and secured to a vehicle body panel P by screwing a bolt into a bolt hole H in the panel P. Therefore, a plurality of electric wires W are together grounded to a vehicle body.
Since it is necessary to segregate and separately remove parts when disassembling a scrapped vehicle, it is required to completely remove from a vehicle body a wire harness that bundles many electric wires.
To remove the electric wire W secured to the vehicle body panel P by the bolt B, the bolt B must be removed from the panel P. In the operation of removing the wire harness from the vehicle body panel P, a hook attached to an end of a crane usually hooks the wire harness and draws the wire harness from the vehicle body. It is very troublesome and time consuming to remove the bolts one by one. Accordingly, the operation of removing the bolts from the vehicle body is usually not performed.
Therefore, when the terminals 1a and 1b are secured to the vehicle body panel P by the bolts B as shown in FIG. 15B, the electric wires W are cut off at their intermediate portions or at connection ends of the terminals 1a and 1b (so-called xe2x80x9cunder-neck positionxe2x80x9d), thereby leaving a part of the electric wires W on the panel P.
In view of the above problem, heretofore, a terminal 2 shown in FIG. 16A has been proposed. The terminal 2 has an attaching portion 2b with a perforated slit 2a. It is possible to easily remove the terminal 2 from the panel P even while the terminal 2 is secured to the panel P by the bolt B, since the slit 2a is broken when the terminal 2 is pulled.
However, when a plurality of terminals 2 are overlapped and secured to the panel P by the bolt B in view of workability and space efficiency, as shown in FIG. 16B, since a lower terminal 2B is covered by an upper terminal 2A, a stress is not transmitted to the slit of the lower terminal 2B when the electric wire W2 crimped in the lower terminal 2B is drawn by a hook. Therefore, instead of the slit breaking, the electric wire W2 breaks.
Additionally, when a slit is formed around the bolt hole, the fixing section is weakened and may be easily broken by a pulling force. However, even a small load such as a vibration of a vehicle may break the slit, thereby lowering the reliability of the connection.
In view of the above problems, an object of the present invention is to provide a terminal that can be secured to a vehicle body reliably while withstanding a vibration of a vehicle, can be removed from the vehicle without leaving any electric wires on the vehicle upon disassembly and/or recycling the vehicle, and can maintain a breakable function even if terminals are overlapped on each other.
In order to solve the above problems, the present invention provides a terminal that includes a base plate section, a fixing section having a bolt-passing hole and extending from the base plate section, and a removable core barrel forming section provided on one side of said base plate section. The insulator cover barrel extends from the base plate section and crimps a sheath of an electric wire. A line of weakness is provided between the removable core barrel forming section and the base plate section. The removable core barrel forming section is oriented with respect to the base plate section such that, when the removable core barrel forming section is bent about the line of weakness, the removable core barrel forming section overlaps a portion of said base plate section and forms a core barrel adjacent to said insulator cover barrel. The core barrel crimps a core of the electric wire. The line of weakness permits the removable core barrel forming section to be detached from the base section while said fixing section remains fixed by a bolt passing through said bolt-passing hole. Therefore, when the electric wire is pulled, such as during scrapping/recycling of an automobile to which the electric wire is attached, the terminal breaks at the line of weakness and the electric wire can be removed from the fixing section.
According to the above structure, the terminal may be subject to work hardening at the line of weakness when the core barrel forming section is folded with respect to the base portion at an angle of about 180 degrees. When a load is subsequently applied to the core barrel forming section in a direction that bends the core barrel forming section back away from the base portion, the terminal is easily broken at the line of weakness.
Therefore, when the electric wire is pulled during disassembly of the vehicle body, a core barrel formed by core barrel forming section and crimped on the electric wire is pulled upwardly, thereby breaking the terminal at the line of weakness. Accordingly, the electric wire can be removed from the vehicle body with the electric wire still being crimped in the core barrel, because the core barrel itself is detached from the terminal at the line of weakness. Consequently, it is unnecessary to remove the bolt to prevent the electric wire from being broken and a piece of the electric wire left attached to the vehicle body.
The terminal of the present invention is used, for example, as a ground terminal secured to a vehicle body by a bolt, or as a terminal crimped on an end of an electric power source line and secured to a bus bar in a junction box by a bolt. Upon disassembling the vehicle body, the electric wire is easily removed from a bolt-fixing section of the terminal without leaving a piece of the electric wire attached to the vehicle body or bus bar.
Since the removable core barrel forming section extends from the base plate section and is folded to overlap the base plate section, in the case where a plurality of terminals are overlapped at their fixing sections and connected to a ground at a single position, the removable portion of the lower terminal is not hidden by the fixing section of the upper terminal and the disassembly work is not inhibited.
The insulator cover barrel is narrower and/or shorter than the core barrel and has a configuration that can easily be opened when the electric wire is pulled during disassembly of the vehicle.
According to the above-described structure, when the electric wire is pulled during disassembly of the vehicle, the insulator cover barrel crimped on the electric wire can be easily removed from the electric wire. Additionally or alternatively, one or more lines of weakness could also be provided to allow the insulator cover barrel to detach from the terminal when subjected to a load due to pulling of the electric wire.
Since the electric wire is crimped in the insulation cover barrel and core barrel, the electric wire is removed from the terminal by a pulling force upon disassembly of the vehicle, but the terminal can hold the electric wire securely against a vibration of the vehicle during normal operation of the vehicle.
One or more slits and/or a groove may be provided at the line of weakness.
That is, the slits and/or groove make the line of weakness weaker against the force that occurs when the electric wire is pulled during disassembly of the vehicle body.
A clamp piece may extend from a side surface of the base plate section opposite the side from which the removable core barrel forming section extends, and the clamp piece may be bent to engage with the folded removable core barrel forming section.
Thus, since the removable core barrel forming portion is held by the clamping piece, during normal use of the vehicle (that is, at times other than the time of disassembling the vehicle), it is possible to keep the core barrel forming portion folded on the base plate section from vibrating and to steadily hold the electric wire on the base plate section.
In another aspect, the present invention provides a terminal in which a removable portion is formed at a distal end of a bolt-fixing section, and is folded at an angle of about 180 degrees with respect to the bolt-fixing section about a line of weakness.
Since the above-described terminals are provided with a removable portion, when an electric wire is pulled during disassembly of an automobile, the pulling force is directly applied to the line of weakness to break the terminal and detach the removable portion of the terminal from the bolt-fixing section of the terminal.
Two terminals may be overlapped, and electric wires connected to the respective terminals may be arranged in parallel with each other. Breakable portions of the respective terminals may be disposed at the opposite sides of overlapped fixing sections.
When the bolt-fixing sections of two or more terminals are to be overlapped, these terminals may be secured to the vehicle body at the given position with concave and convex portions around the bolt-passing holes being engaged with each other.
If two terminals overlapping each other, when two electric wires connected to the terminals are pulled either simultaneously or individually, the pulling force can be applied directly to the respective lines of weakness since the lines of weakness are not overlapped on each other. Consequently, the respective terminals can be reliably removed from the bolt-fixing sections.